Landmark HIV case may be the second person ever to be ‘cured’

A second person may have had his HIV infection wiped out after receiving a bone marrow transplant to treat his cancer. Until now there had only been one previous such case, a man known as the “Berlin patient”, who received a similar cancer treatment over a decade ago.

Such treatment can’t be used for people with HIV who don’t have cancer, because bone marrow transplants carry considerable risks and are only used as a last resort. But the fact that the approach seems to have worked for a second time suggests the Berlin patient was no fluke, and could point the way to other strategies for a cure, says Ravindra Gupta at the University of Cambridge.

About a year after the “London patient” received his bone marrow transplant, he was advised to stop taking his antiviral medicines. It is now 18 months since then and there has been no return of the virus. Although it is too early to call it a cure, Gupta says it would be considered so after three to four years. “The signs are promising,” he says.

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HIV infects cells of the immune system, which are made in the bone marrow. Although it was once nearly always fatal, today people can take antiviral drugs that stop HIV from multiplying. These eliminate the virus from blood and sexual fluids, but small amounts hide out in dormant immune cells in organs such as the spleen. If someone stops taking their antiviral drugs, the levels of virus in their blood go back up again, and they would eventually die.

The Berlin patient was treated in 2007. Diagnosed with leukaemia, a cancer of immune cells, he had a bone marrow transplant. This involves killing nearly all of someone’s immune cells with radiotherapy or toxic drugs, then replacing them with cells from a donor. His doctors chose a donor who was naturally resistant to catching HIV because of a mutation in a gene called CCR5, which is found in a small minority of people in Western Europe and is even rarer elsewhere.

Genetic resistance

Now Gupta and his colleagues appear to have repeated this feat. The London patient had Hodgkin’s lymphoma, another form of cancer in immune cells. The team found him a bone marrow donor with the CCR5 mutation.

Importantly, in this case the man didn’t need such a harsh treatment for killing his immune cells – he had milder drugs and, unlike the Berlin patient, he had no radiotherapy. “It’s fantastic not to have to give that,” says Gupta. The Berlin patient faced a 50 per cent risk of death from his treatments. The London patient was thought to have a 10 to 20 per cent risk.

“Now we know the first case wasn’t an anomaly, but is something that can be shared,” says Gupta, who was involved in treating the London patient while working at University College London.

Ravindra Gupta’s team treated the “London patient”

Jane Stockdale/The New York Times/Redux/Eyevine

“While there was only one case there was always uncertainty,” says Jonathan Weber of Imperial College London, who wasn’t involved in the work. “This shows it’s reproducible.”

Recently a researcher in China called He Jiankui used gene editing on human embryos to try to create babies who will be resistant to catching HIV by giving them the CCR5 mutation. His work has been widely criticised and his research programme has now been stopped.